小英雄麦特 第四季It's Dad's birthday and Matt has a problem. How can Grandpa Alfred send Harry his traditional 'happy returns' of the day from his far-flung prison realm? And there are also unhappy returns in the shape of the turbo-charged Cyber-Racer, hell-bent on plunging Carnival City into never-ending darkness! The race is on but when the chequered flag falls, who will be left standing?